diff --git a/compiler/rustc_resolve/src/check_unused.rs b/compiler/rustc_resolve/src/check_unused.rs index 0579e91c0d6ec..e0b2adb3fc953 100644 --- a/compiler/rustc_resolve/src/check_unused.rs +++ b/compiler/rustc_resolve/src/check_unused.rs @@ -193,6 +193,16 @@ impl<'a, 'ra, 'tcx> UnusedImportCheckVisitor<'a, 'ra, 'tcx> { continue; } + let module = self + .r + .get_nearest_non_block_module(self.r.local_def_id(extern_crate.id).to_def_id()); + if module.no_implicit_prelude { + // If the module has `no_implicit_prelude`, then we don't suggest + // replacing the extern crate with a use, as it would not be + // inserted into the prelude. User writes `extern` style deliberately. + continue; + } + let vis_span = extern_crate .vis_span .find_ancestor_inside(extern_crate.span) diff --git a/tests/ui/resolve/extern-crate-lint-issue-141785.rs b/tests/ui/resolve/extern-crate-lint-issue-141785.rs new file mode 100644 index 0000000000000..8d044d666df4f --- /dev/null +++ b/tests/ui/resolve/extern-crate-lint-issue-141785.rs @@ -0,0 +1,11 @@ +//@ check-pass +//@ edition:2018 + +#![no_implicit_prelude] +#![warn(unused_extern_crates)] + +extern crate std; +fn main() { + let r = 1u16..10; + std::println!("{:?}", r.is_empty()); +}